Producing small castings by the lost wax method has been disclosed in prior U.S. patents such as U.S. Pat. No. 3,648,760, issued Mar. 14, 1972 and No. 3,985,178, issued Oct. 12, 1976. These patents also disclose the use of plastics and wax having different melting points to aid in forming a suitable metal receiving cavity.
Where the castings are in the form of a plurality of very small articles such as is common in dental restorations, jewelry or the like, all of which are to be cast at the same time, prior art devices, require a great amount of time consuming skill particularly where the models are closely grouped within the casting flask.
Accordingly, it is an object of the present invention to provide a precision investment casting apparatus which will greatly facilitate the casting of a substantial number of small articles within a single flask.
Another object of the present invention is to provide casting apparatus which will lend itself to a variety of casting operations.
A further object of the present invention is to provide casting apparatus which may be assembled by persons with less skill than required for previous systems.
A feature of the present invention is its use of a combined plug and socket member which can be assembled to form a sprue as the casting tree is built up.
Another feature of the present invention is its flask construction which aids in removing the flask from the lost wax embedment.